The present invention is directed to an endless flexible seamed belt having improved seam quality and smoothness with substantially no thickness differential between the seamed portion of the belt and the adjacent main body of the belt, and having a strength enhancing bond formed in voids between mutually mating elements of the belt of a material which is chemically and physically compatible with the material of the coating layers of the belt. In embodiments, the present invention relates to xerographic components comprising an adhesive formed between mutually mating elements of a seam, wherein the adhesive comprises an unsaturated carbonate material. The present invention, in embodiments, allows for relatively fast preparation and manufacture of xerographic components which reduces seam fabrication cycle time. In addition, the adhesive is compatible with the belt materials including, in preferred embodiments, a polyester substrate, a transport layer, and anti-curl back coating. Further, in embodiments, the seam has a decreased surface roughness which results in a decrease in cleaning blade wear, an increase in cleaning efficiency, and greater stability in belt cycling motion quality. In addition, in embodiments, the seam shape is superior in continuity resulting in a decrease in cracking and delamination failure problems. Furthermore, the seam has increased seaming bonding strength to decrease tearing as well as enhance the seam's tensile rupture resistance. Moreover, in embodiments, the seam has a decreased inherent and virtually nil seam height which allows for superior cleaning efficiency and superior hybrid scavengeless development efficiency. Furthermore, the adhesive chosen to bond the ends of the belt crosslinks, resulting in little or no shrinkage at the crevice of the seam.
In a typical electrostatographic reproducing apparatus such as electrophotographic imaging system utilizing a photoreceptor, a light image of an original to be copied is recorded in the form of an electrostatic latent image upon a photosensitive member and the latent image is subsequently rendered visible by the application of electroscopic thermoplastic resin particles which are commonly referred to as toner. Generally, the electrostatic latent image is developed by bringing a developer mixture into contact therewith. Toner particles are attracted from the carrier granules to the latent image forming a toner powder image thereon. Alternatively, a liquid developer material may be employed. After the toner particles have been deposited on the photoconductive surface, in image configuration, the developed image is transferred to a receiving copy substrate. The image is subsequently fused to a copy substrate by the application of heat in combination with pressure.
Belts, sheets, films and the like are important to the xerographic process. In addition, belt function is very much affected by the seam of the belt. For example, belts formed according to known butting or overlapping techniques provide a bump or other discontinuity in the belt surface leading to a height differential between adjacent portions of the belt, of 0.010 inches or more depending on the belt thickness, which leads to performance failure in many applications. A bump, surface irregularity, or other discontinuity in the seam of the belt may disturb the tuck of the cleaning blade as it makes intimate contact with the photoconductive member surface to effect residual toner and debris removal. This may allow toner to pass under the blade and not be cleaned. Furthermore, seams having differential heights may when subjected to repeated striking by cleaning blades, cause photoconductive member cycling speed disturbance which affects the crucial photoconductive belt motion quality. Moreover, seams with a bump or any morphological defects can facilitate the untransferred, residual toner to be trapped in the sites of seam surface irregularities. The seam of a photoreceptor belt which is repeatedly subjected to the striking action by a cleaning blade under machine functioning conditions has triggered the development of pre-mature seam delamination failure. As a result, both the cleaning life of the blade and the overall service life of the photoreceptor belt can be greatly diminished. In addition, the copy quality of image printout can be degraded. Moreover, such irregularities in seam height provide vibrational noise in xerographic development which disturb the toner image on the belt and degrades resolution and transfer of the toner image to the final copy sheet. This is particularly prevalent in those applications requiring the application of multiple color layers of liquid or dry developer on a photoreceptor belt, which are subsequently transferred to a final copy sheet. In addition, the discontinuity in belt thickness due to the presence of an excessive seam height yields variances of mechanical strength in the belt as well as reducing the fatigue flex life of the seam when cycling over the belt module support rollers. Further, the seam discontinuity or bump in such a belt may result in inaccurate image registration during development, inaccurate belt tracking and overall deterioration of motion quality, as a result of the translating vibrations.
U.S. Pat. No. 5,487,707 relates to an endless flexible seamed belt comprising puzzle cut members, and further comprising a bonding between adjacent surfaces by an ultraviolet cured adhesive.
U.S. Pat. No. 5,514,436 relates to an endless flexible seamed belt having puzzle cut seams and wherein the seam is of a substantially uniform thickness as the rest of the belt.
U.S. Pat. No. 5,549,193 relates to an endless flexible seamed belt formed comprising puzzle cut members, wherein at last one receptacle has a substantial depth in a portion of the belt material at the belt ends.
Although the above references teach interlocking seams which provide for decreased inherent seam height, increased seam strength, decreased surface roughness at the seam, and increased continuity at the seam, there still exists a need for a seam which has increased seam bonding strength to prevent premature delamination, tearing or rupture. Further, there exists a need for a flexible belt having a seam, wherein the belt is thin and has improved surface profile to suppress force cleaning blade/seam interaction as well as eliminate residual toner/debris/dirt entrapping. In addition, it is desired to provide a belt which is easily and speedily fabricated. There further exists a need for an adhesive seaming material which is compatible with the belt materials, including the substrate and the outer layer(s) and, in preferred embodiments, is useful for flexible photoreceptor belts employing seams such as, for example, puzzle cut seams. Moreover, it is desired to provide a seam with virtual nil thickness differential with the main body of the belt, as well as a belt with good tensile and bending flexibility. Furthermore, it is desired to provide an adhesive, which when placed in the crevice between belt ends, will result in little or no shrinkage.